Dildabek, G. and Tengayeva, A. (2016) “Existence of eigenvalues of problem with shift for an equation of parabolic-hyperbolic type”, Bulletin of the Karaganda University. Mathematics Series, 2(82), pp. 48–55. Available at: https://mts.buketov.edu.kz/mathematics-vestnik/article/view/98 (Accessed: 8 December 2025).